Loricraft Stabilised Power Supply Units

Garrard501 and 301/401 Archivist

Background - Most hi-fi equipment requires a stable, specified, electrical supply. Unfortunately the consumer rarely if ever gets this, and, as the supply is never seen, the user is unaware of how far the actual supply has drifted from the specified volts/cycles. Here is a dynamic view of the actual UK power grid supply at the moment. It has to balance the needs of the consumers at any time by changing the amount of power generation. Check the change at half time in a big soccer game when people make a cup of tea etc.. Most national electical grids perform much worse than the UK system.

The Loricraft Power Supply Units (PSU) have been designed to produce a very stable supply of the specified power even as the National Grid fluctuates. The beneficial effect on the performance of the equipment powered by the supply has been well documented. The PSUs are built to work with all the national power grids and can even mimic a foreign grid enabling a UK specification turntable to be run in the USA without modification.

For nearly 10 years, Loricraft Audio have produced mains voltage power supply units. Put simply these units produce pure mains voltage AC waveforms at very precise frequencies normally 50 Hz or 60 Hz with very stable voltage and low distortion regardless of the quality of the domestic mains supply. Originally these supplies were intended for use with Garrard 301 and 401 turntables, and the new Garrard501. It is now accepted that they improve the performance of other equipment, and increasingly we supply them for use with the source components such as CD players, tapedecks, radio tuners and preamplifiers.

Following the success of the original PSU45, PSU 80 and the Garrard501 power supplies, new versions have been developed and recent reviews have shown the magnitude of the improvement they can bring to the performance of classic turntables.

Audio Magazine have just published a series of three articles showing the restoratation of a Garrard 301 by Loricraft Audio from purchase through to great laboratory test results . The Garrard 301 was powered with the best power supply we have ever made for any historical Garrard, the new Garrard 301/401 Archivist - developed from the Reference mains regenerating 501 PSU designed for the Garrard501 turntable. If you own a Garrard 301, a Garrard 401 or a Thorens 124 you need this outstanding new power supply! By taking control of the turnable speed it reduces noise and improves performance. It could be your best update. Martina's first two demonstrations of the PSU Archivist in Germany resulted in sales. You should really ask for more information about the new Generator PSU Archivist at our Internet Shop or your local dealer!

PSU 301 AR

The price of the PSU 301 AR from 20 April 2008 is £2552.34 plus VAT.

In 2006 Germany's Hi Fi magazine Audio requested a special power supply inspired by the PSU 501 supplied with our Garrard 501 turntable. As they rightly understood, much of the excellence of the 501 is derived from it's power supply. "Audio" also asked for a specially made version for a restored Garrard 301 fitted in the same plinth system design as the 501. In this way they could compare the modern 501 and the vintage 301. This showed that the 501 is a perfected version of the 301 and 401 designs and that the power supply is a large part of it. We have to thank " Audio " as without this very specific request it is probable that a power supply of this sophistication would never have been produced.

To put it as simple as possible. The incoming mains electricity is converted into DC electricity (like a huge battery). The desired mains AC electricity is then regenerated to a perfect version of the 230V an voltage standard. Distortion of any kind is kept to 1/1000th part (typically half that or better). These limits are the ones held to be beyond audible limits, therefore perfect. Very fine control of output voltage allows torque adjustment. The early 301 was intended for mono only. By setting to the lowest torque setting stereo with a low playing weight cartridge is possible. Conversely an early 401 needs full output if a high playing weight is used.

The speed adjustment range of the PSU 301 AR is as follows. REF a fixed 50 Hz output. ST to adjust all modern records. The other ranges -2,-1 ,1 , 2 are for acoustically recorded 78's .

The PSU 301 AR is a more complicated version of the PSU 501 supplied with the Garrard 501 turntable which we manufacture. We felt that the price of the PSU 301 AR was probably beyond the pocket of the majority of our fellow Garrard users and so we decided to try to design a less complex version which would deliver the stablity the normal customer would want but not necessarily all speed variants of the more expensive version. This is the PSU 401 AR.

PSU 301 AR can take upwards of a week to complete as, like much of what we do, it is produced by hand. Most of this time is taken up with painstaking adjustment. The new PSU 401 is as near as Loricraft will ever get to a mass production product . It mimics the performance of PSU 301 AR whilst using the dreaded crystal oscillator. How have we been able to do this when in the past we couldn't? The answer also comes from the PSU 301 AR. Each one of these is tested on a spectrum analyser as well as an oscilloscope. As we have acquired this test equipment we can use it to model "the perfect" synthesis of more expensive design in the crystal version.

How do the two designs differ?

Firstly PSU 401 AR costs less than half the price of the PSU 301 AR. It differs considerably from the PSU 301 AR and 90% of its circuitry has a new and unique design. It has a fixed frequency output of 50 Hz with variable voltage output (200 to 230 VAC). Distortion is
about 10 dB up from PSU301AR, however this is still very low at -56 dB. Stability is excellent as would be expected. We prefer the 50 Hz option. Even if we could make a 60 Hz version we wouldn't do it willingly as 50 Hz produces less audible rumble. We also advocate 230 V which is an option on all Garrards. The PSU 's can be specified 115 or 230 V as input and likewise as output. The input frequency is not important as the PSU's have their own oscillators.

Finally, the PSU 301 AR offers true archivist performance, namely it will allow all recordings ever made to be played at the correct speed.
PSU 401 AR suits recordings made after 1930. PSU 301 AR has the additional advantage of allowing the Garrard 301 and 401 to be
operated without the eddy current break, like the Garrard 501.

Anyone wishing to audition the power suppliers is welcome to visit us at Loricraft where we will be happy to demonstrate the advantages. Put simply, it delivers a standard of performance better than mains electricity can achieve, and once set it never changes.

These units are very versatile and can be supplied to stabilise any national supply. They can also enable UK specification Garrard 301 and 401 turntables, with strobes, to operate normally in the USA. This needs to be specified when the order is confirmed.